To combat the spreading invasive species and to prevent the introduction of further species in the Great Lakes, a series of policy's must be engaged to combat the spread of invasive species. Invasive species such as the zebra mussel were introduced by oceangoing ships dumping ballast water into the Great Lakes. Perhaps requiring the filtering of ballast water before it is dumped would be an effective compromise to be considered. Already, some areas have regulations requiring you to clean your boat before moving it from one lake to another. While this is an issue for ocean-going vessels which tend to be massive, it is a good measure for recreational boaters and fishers, and as such should be implemented as a standard measure. The greatest threat we have to the Great Lakes, and inland lakes would be Zebra mussels, and these policy's would prevent them from spreading to more inland lakes from careless recreational boaters.
On another front, the Asian Carp threat has led to some more extreme policy's and actions that are more that questionable. The dumping of fish poison into vast stretches of rivers to kill the fish, and the use of electric fence barriers are good examples of the measures we have taken to slow their advance. The question we are faced with is if we can justify killing off innocent native fish species to prevent the advance of an invasive species, for the use of fish poison will yield that result.
While there are always options to combat invasive species, the problem is coming up with a policy that can be implemented without destroying many other species, or interfering greatly with human existence. If it comes down to a choice, humans will always choose themselves first. All we can do is try to encourage those in power to make more environmentally friendly decisions and take whatever actions we can to better our local ecosystems. Invasive species are here to stay, there's no defeating them, but with a great deal of work, we may be able to prevent them from wreaking havoc and destroying the delicate balance of the Great Lakes ecosystems.
Sources:
http://www.skuld.com/News/Archive/News-Archive/2003/-Environmental-Pollution-Caused-by-Dumping-Ballast-Water-under-Turkish-Law-and-Practice/
http://environmentreport.org/show.php?showID=632
http://www.tcdailyplanet.net/blog/hindsight/clean-your-boats-minnesotans-get-it-why-doesn-t-epa
http://articles.chicagotribune.com/2012-03-27/news/ct-met-carp-microtoxins-20120327_1_mississippi-river-basin-poison-pill-invasive-species
Wednesday, May 9, 2012
Wednesday, April 18, 2012
Invasive species and waste
In the Great Lakes, we have two problems. The first in that in the past, raw sewage has been dumped into the Great Lakes from overflowing sewers and deep tunnels. Our waste treatment plants cannot handle the water pumped in during storms, so in the past sewage has been dumped untreated into the Lakes. This is a huge environmental problem as this waste is hazardous, disease is a very real threat. The 1993 Cryptosporidium outbreak was proof enough of this. The threat of waste water being dumped into the Great Lakes is a very real threat to the health of all those who call the Great Lakes region home. The second problem facing our Great Lakes is invasive species, threatening the survival of local species.
So how do these two problems relate to each other? A notorious invasive species, Asian carp, was introduced to the United States by southern fisheries as an experimental waste treatment program. The fish eventually escaped (or were released), and have spread north the the very edge of our Great Lakes spreading like wildfire. Why are Asian carp such a threat? Asian carp are large fish that consume large amounts of plankton, detritus, and will even consume sewage. The are a fish that will eat anything and can live in terrible water conditions. They breed in huge numbers, and when fully grown have few if any predators. Asian carp can choke out all other composition in rivers and lakes by consuming the lowest level of the food chain more efficiently than native species can hope to compete with.
As if Asian carp were not bad enough, zebra mussels are even more efficient at cleaning water. While they can also remove pollution, the fact is they can sterilize a lake. They have already wreaked havoc in Lake Erie and are spreading like a plague. Few predators and rapid population growth combined with the ability to filter water leaving almost nothing for other animals to consume means this mussel poses a massive threat to the stability of the Great Lakes.
There are positives and negatives to invasive species. They can deal with pollution and clean our lakes. That is a positive. The negative is that they are so efficient at it that they may very well sterilize the Great Lakes leaving behind sterile pools of water incapable of supporting life. The threat invasive species pose is a very real threat that cannot be ignored.
Sources:
http://www.mkelgbthist.org/events/health/crypto.htm
http://eattheinvaders.org/asian-carp/
http://www.protectyourwaters.net/hitchhikers/mollusks_zebra_mussel.php
So how do these two problems relate to each other? A notorious invasive species, Asian carp, was introduced to the United States by southern fisheries as an experimental waste treatment program. The fish eventually escaped (or were released), and have spread north the the very edge of our Great Lakes spreading like wildfire. Why are Asian carp such a threat? Asian carp are large fish that consume large amounts of plankton, detritus, and will even consume sewage. The are a fish that will eat anything and can live in terrible water conditions. They breed in huge numbers, and when fully grown have few if any predators. Asian carp can choke out all other composition in rivers and lakes by consuming the lowest level of the food chain more efficiently than native species can hope to compete with.
As if Asian carp were not bad enough, zebra mussels are even more efficient at cleaning water. While they can also remove pollution, the fact is they can sterilize a lake. They have already wreaked havoc in Lake Erie and are spreading like a plague. Few predators and rapid population growth combined with the ability to filter water leaving almost nothing for other animals to consume means this mussel poses a massive threat to the stability of the Great Lakes.
There are positives and negatives to invasive species. They can deal with pollution and clean our lakes. That is a positive. The negative is that they are so efficient at it that they may very well sterilize the Great Lakes leaving behind sterile pools of water incapable of supporting life. The threat invasive species pose is a very real threat that cannot be ignored.
Sources:
http://www.mkelgbthist.org/events/health/crypto.htm
http://eattheinvaders.org/asian-carp/
http://www.protectyourwaters.net/hitchhikers/mollusks_zebra_mussel.php
Water use, Pollution, and Invasive species
In todays blog I will address the issues of Water use, and pollution and their effects on invasive species. Invasive species are often brought in through human activity. Some species cling to boats or can be found in ballast tanks, others were released through sheer human stupidity. Our Great Lakes are connected to the ocean through the St. Laurence Seaway, a series of man-made locks that allow ships to gain access to the Great Lakes from the Atlantic Ocean. Shipping is a form of water use, and the locks use a lot of water to raise or lower a ship to the level of the next lock to allow movement up or down the system. What does this have to do with invasive species? The ships traveling this canal are ocean going ships that carry ocean water in their ballast tanks. When emptied, any animals that may have been trapped in the tanks are dumped into the Great Lakes. Zebra mussels, Sea Lamprey, and other small invasive species may have been introduced to the Great Lakes in this manner.
Pollution represents a significant problem to our Great Lakes. The Great Lakes hold a vast amount of drinkable fresh water. If this water becomes polluted, this has consequences for human life near the Great Lakes. On the invasive species front, pollution is more a problem for native species than the hordes of invasive species on the rise. Raw sewage dumped into the lake may sound like a bad thing, and for human health and the health of many native species it is, however there is one species that was introduced to the United States to combat that very thing. Asian carp are bottom feeders, consuming plankton, detritus, and quite possibly raw sewage. They reproduce in vast numbers and consume large amounts of food. Wherever these fish go they choke out all other competition by growing large, breeding fast, and consuming anything and everything. If these fish are not bad enough let us add a small invasive species called the zebra mussel. This little filter feeder also reproduces fast and in large numbers, spreading like a plague. These mussels suck up water, remove any particles from it and release clean water. While you might ask is this a bad thing to have clean water, the answer is yes it is bad. Those small particles, ditritus, and plankton represent the lowest level of the food chain. These mussels muscle in on the lowest level of the food chain, wiping out all other compitition by out competing them for food. These nasty little critters can steralize a lake if left unchecked. Pollution is more likely to feed these critters than hurt them.
To conclude, Pollution and human water use cause many problems for native species, but for at least two of the invasive species threatening the Great Lakes, pollution may prove to fuel the fire. Animals that can consume raw sewage and spread like a plague in vast numbers are a larger threat than the pollution they themselves can consume.
Sources:
http://www.greatlakes-seaway.com/en/
http://www.oar.noaa.gov/spotlite/archive/spot_zebramussels.html
http://eattheinvaders.org/asian-carp/
Pollution represents a significant problem to our Great Lakes. The Great Lakes hold a vast amount of drinkable fresh water. If this water becomes polluted, this has consequences for human life near the Great Lakes. On the invasive species front, pollution is more a problem for native species than the hordes of invasive species on the rise. Raw sewage dumped into the lake may sound like a bad thing, and for human health and the health of many native species it is, however there is one species that was introduced to the United States to combat that very thing. Asian carp are bottom feeders, consuming plankton, detritus, and quite possibly raw sewage. They reproduce in vast numbers and consume large amounts of food. Wherever these fish go they choke out all other competition by growing large, breeding fast, and consuming anything and everything. If these fish are not bad enough let us add a small invasive species called the zebra mussel. This little filter feeder also reproduces fast and in large numbers, spreading like a plague. These mussels suck up water, remove any particles from it and release clean water. While you might ask is this a bad thing to have clean water, the answer is yes it is bad. Those small particles, ditritus, and plankton represent the lowest level of the food chain. These mussels muscle in on the lowest level of the food chain, wiping out all other compitition by out competing them for food. These nasty little critters can steralize a lake if left unchecked. Pollution is more likely to feed these critters than hurt them.
To conclude, Pollution and human water use cause many problems for native species, but for at least two of the invasive species threatening the Great Lakes, pollution may prove to fuel the fire. Animals that can consume raw sewage and spread like a plague in vast numbers are a larger threat than the pollution they themselves can consume.
Sources:
http://www.greatlakes-seaway.com/en/
http://www.oar.noaa.gov/spotlite/archive/spot_zebramussels.html
http://eattheinvaders.org/asian-carp/
Wednesday, March 21, 2012
Invasive species and Climate
In this blog we will look at how climate relates to invasive species. The success of a species relies on its ability to adapt to its environment, and its climate. While species may face predators and competition, the largest threat to the success or failure of a species is that which nature throws at it. Whenever you see a climate shift, for instance an ice age, or a warming period, you will always see an increase in extinction rates as species that are not well adapted die off. Invasive species have several advantages over native species in terms of predators. But would this be enough to help them escape the fact that they themselves are in an alien environment that they did not evolve in? This is a question we can only speculate on, however, if we look at invasive species adaption to their new environments we can get clues. The Asian carp for example is slowly working its way towards the Great Lakes. The Great Lakes are a chain of cold freshwater lakes connected making a huge diverse community. The Asian carp come from similar cold freshwater origins, so they are already well adapted to the cold climate. They may not be specifically evolved to deal with the climate here, but they come from a similar place. As such they stand a good chance of surviving here. With a lack of predators and evolution in a similar climate, the Asian carp, if they arrive seem to be set up to survive and become a new permanent resident of the great lakes community.
Sources:
http://www.glfc.org/fishmgmt/carp.php
http://www.endangeredspeciesinternational.org/overview.html
Sources:
http://www.glfc.org/fishmgmt/carp.php
http://www.endangeredspeciesinternational.org/overview.html
Restoration Ecology
Restoration Ecology has to do with restoring damaged ecosystems to a healthy state. This blog will discuss how invasive species tie in with Restoration Ecology. The major issue with invasive species is that they tend to be overly successful due to a lack of natural predators. The most successful invasive species are those that adapt well, or those that manage to wipe out the competition. Arguably the largest threat to the Great Lakes, both in terms of actual size and potential threat is the Asian carp. This fish when fully grown will have few if any naturally occurring predators in the Great Lakes. The only shred of good news is that certain native fish prey on a fish called shad which apparently looks similar to Asian carp less than a year in age. (www.mlive.com) So, the Asian carp will at least have some check on their explosive growth. (Asian Carp breed in vast numbers, allowing explosive population growth) While there is no check on the adult population, the juveniles and eggs can be kept in check by maintaining a high population of predatory native fish. (which will be encouraged by a new food source) So Asian carp could in fact be kept in check in the great lakes. While its not exactly restoration of the natural ecosystem, its better than a total collapse.
While the Asian carp threat has some hope, another looming threat may prove to be as bad if not worse than Asian carp. Zebra mussels may not have the size of Asian carp, but they make up for it by reproducing faster in large numbers and choking out all other competition consuming the lowest level of the food chain. According to fi.biology.usgs.gov, the zebra mussels do in fact have a few predators, but a few species of fish and some ducks are not going to make a significant impact on the population of zebra mussels given their sheer numbers and reproductive rates. This species will probably require human intervention to prevent it from taking over our lakes.
Sources:
http://www.mlive.com/opinion/muskegon/index.ssf/2010/01/we_can_beat_asian_carp_threat.html
http://fl.biology.usgs.gov/Nonindigenous_Species/Zebra_mussel_FAQs/zebra_mussel_faqs.html
While the Asian carp threat has some hope, another looming threat may prove to be as bad if not worse than Asian carp. Zebra mussels may not have the size of Asian carp, but they make up for it by reproducing faster in large numbers and choking out all other competition consuming the lowest level of the food chain. According to fi.biology.usgs.gov, the zebra mussels do in fact have a few predators, but a few species of fish and some ducks are not going to make a significant impact on the population of zebra mussels given their sheer numbers and reproductive rates. This species will probably require human intervention to prevent it from taking over our lakes.
Sources:
http://www.mlive.com/opinion/muskegon/index.ssf/2010/01/we_can_beat_asian_carp_threat.html
http://fl.biology.usgs.gov/Nonindigenous_Species/Zebra_mussel_FAQs/zebra_mussel_faqs.html
Wednesday, March 14, 2012
Food and Hunger
In today's blog I will be going over the effects of invasive species on Food and Hunger. Invasive species are not the greatest threat to the food security of humans near the great lakes as most people who live near the great lakes do not rely on fish or food directly from the lakes as a primary food source. The real threat to humans is not to food, but to commercial fishing. The invasive species would be a far greater threat if America was a third world nation without the availability of food in the united states. Fish caught from fresh water are not a major part of the American diet and this is only likely to effect fishers directly. Fresh water fish are not consumed as often as salt water fish due to high mercury levels so this will not effect the diets of Americans significantly. (abcnews.go.com) The real problem is when you look at the greater effects of invasive species.
Invasive species can wipe out entire ecosystems if left unchecked, and the Great Lakes have their share of invasive species that threaten their stability. Asian Carp, Sea Lamprey, Zebra Mussels, and a wide range of other invasive species threaten our lakes. These invasive species consume phytoplankton which is the basis of the aquatic food chain. Animals like the Asian Carp can consume 10 percent of their body weight a day (livescience.com) and breed at alarming rates. With few if any predators limiting their explosive growth, Asian Carp are a significant threat to the Great Lakes. Wiping out the base of a food chain can cause a collapse leading to mass extinction, potentially taking out entire ecosystems. If this happens in the Great Lakes, it would expand outward from the lakes to the terrestrial animals that depend on freshwater for food. Few terrestrial animals if any rely on the great lakes as a major dietary component, so it is unlikely that many terrestrial animals would go extinct, however it could shift diets of animals and force them to adapt in unpredictable ways.
To conclude this blog, invasive species in the Great Lakes are not likely to effect the human food supply significantly. Rather, they are a threat to the native species in the Great Lakes, and terrestrial species that rely on food from the Great Lakes. The threat to humans is an economic threat rather than a threat of starvation.
http://www.livescience.com/8364-asian-carp-fearsome.html
http://abcnews.go.com/GMA/mercury-found-fish-streams-country/story?id=8369324
Invasive species can wipe out entire ecosystems if left unchecked, and the Great Lakes have their share of invasive species that threaten their stability. Asian Carp, Sea Lamprey, Zebra Mussels, and a wide range of other invasive species threaten our lakes. These invasive species consume phytoplankton which is the basis of the aquatic food chain. Animals like the Asian Carp can consume 10 percent of their body weight a day (livescience.com) and breed at alarming rates. With few if any predators limiting their explosive growth, Asian Carp are a significant threat to the Great Lakes. Wiping out the base of a food chain can cause a collapse leading to mass extinction, potentially taking out entire ecosystems. If this happens in the Great Lakes, it would expand outward from the lakes to the terrestrial animals that depend on freshwater for food. Few terrestrial animals if any rely on the great lakes as a major dietary component, so it is unlikely that many terrestrial animals would go extinct, however it could shift diets of animals and force them to adapt in unpredictable ways.
To conclude this blog, invasive species in the Great Lakes are not likely to effect the human food supply significantly. Rather, they are a threat to the native species in the Great Lakes, and terrestrial species that rely on food from the Great Lakes. The threat to humans is an economic threat rather than a threat of starvation.
http://www.livescience.com/8364-asian-carp-fearsome.html
http://abcnews.go.com/GMA/mercury-found-fish-streams-country/story?id=8369324
Tuesday, February 14, 2012
Population biology in the Great Lakes
The subject of todays blog is population biology in the great lakes. In todays blog, we will go over the basics of what population biology is, what it means in regards to the great lakes, and how invasive species effect it. Now let us begin with a description of what population biology is. Population biology, according to Environmental Science A Global Concern's authors William P. Cunningham and Mary Ann Cunningham, "is the science of modeling changes in species abundance." (Environmental Science A Global Concern p.117).
So what does Population biology have to do with the great lakes? Overfishing and loss of biodiversity are major controversial issues in the world, and the fact is that we are having an impact on the world. Humans are exploiting the limited resources offered up by our planet, and consuming them at an alarming rate. It has been said many times that fish stocks are being depleted, but what does this mean? When a fish stock reaches a certain level and human consumption exceeds the fishes ability to replace the individuals that are caught for human consumption, the stock depletes growing smaller and smaller until it is wiped out or a new fish is chosen. All over the world this is happening, but what is happening in the Great Lakes? Sadly, fish stocks in the great lakes are being depleted, fishing, pollution, and invasive species are taking their toll on the native fish that inhabit our Lakes. According to www.rff.org, the sea lamprey alone crushed the populations of lake trout. It is likely other fish were effected similarly. One invasive species managed to bring a local population to its knees. This coupled with fishing, pollution, and the combined pressure of invasive species could spell doom for local fish stocks.
So the final question his how do invasive species effect population biology in the great lakes. The fact is that invasive species such as Asian Carp breed at a rapid rate and consume the food other fish need to survive. Zebra mussels filter out the smallest particles of food leaving behind sterile water incapable of supporting life. Sea Lampreys are wiping out the populations of larger fish further disrupting the natural balance of the great lakes. All these invasive species are causing Native populations to plummet. The Great Lakes themselves are in shock. If things continue as they are, they will flat line, and there may be no reviving our Lakes. The flip side of the coin here is although Native species are on the decline, these successful invasive species are breeding quite fast and replacing the old fish stock in a sense. According to www.npr.org, the asian carp could be used as a potential food source and are even now being harvested. Unlike traditional fish stocks, this invasive species will not likely have limitations to stock as the breed quite rapidly and have the advantage of a lack of predators. While this is good news for depleted fish stocks, it is also bad news as the asian carp are replacing our Native fish populations. Only time will tell what will happen, but at present things are looking grim for the Great Lakes.
Resources:
Environmental Science A Global Concern by William P. Cunningham and Mary Ann Cunningham
http://www.rff.org/Publications/WPC/Pages/03_23_09_RestoringGreatLakesEcosystemsWorththeCost.aspx
http://www.npr.org/templates/story/story.php?storyId=5542199
So what does Population biology have to do with the great lakes? Overfishing and loss of biodiversity are major controversial issues in the world, and the fact is that we are having an impact on the world. Humans are exploiting the limited resources offered up by our planet, and consuming them at an alarming rate. It has been said many times that fish stocks are being depleted, but what does this mean? When a fish stock reaches a certain level and human consumption exceeds the fishes ability to replace the individuals that are caught for human consumption, the stock depletes growing smaller and smaller until it is wiped out or a new fish is chosen. All over the world this is happening, but what is happening in the Great Lakes? Sadly, fish stocks in the great lakes are being depleted, fishing, pollution, and invasive species are taking their toll on the native fish that inhabit our Lakes. According to www.rff.org, the sea lamprey alone crushed the populations of lake trout. It is likely other fish were effected similarly. One invasive species managed to bring a local population to its knees. This coupled with fishing, pollution, and the combined pressure of invasive species could spell doom for local fish stocks.
So the final question his how do invasive species effect population biology in the great lakes. The fact is that invasive species such as Asian Carp breed at a rapid rate and consume the food other fish need to survive. Zebra mussels filter out the smallest particles of food leaving behind sterile water incapable of supporting life. Sea Lampreys are wiping out the populations of larger fish further disrupting the natural balance of the great lakes. All these invasive species are causing Native populations to plummet. The Great Lakes themselves are in shock. If things continue as they are, they will flat line, and there may be no reviving our Lakes. The flip side of the coin here is although Native species are on the decline, these successful invasive species are breeding quite fast and replacing the old fish stock in a sense. According to www.npr.org, the asian carp could be used as a potential food source and are even now being harvested. Unlike traditional fish stocks, this invasive species will not likely have limitations to stock as the breed quite rapidly and have the advantage of a lack of predators. While this is good news for depleted fish stocks, it is also bad news as the asian carp are replacing our Native fish populations. Only time will tell what will happen, but at present things are looking grim for the Great Lakes.
Resources:
Environmental Science A Global Concern by William P. Cunningham and Mary Ann Cunningham
http://www.rff.org/Publications/WPC/Pages/03_23_09_RestoringGreatLakesEcosystemsWorththeCost.aspx
http://www.npr.org/templates/story/story.php?storyId=5542199
Wednesday, February 8, 2012
Biological Communities and the long term effect of invasive species
In today's blog, the following topics will be discussed: Biological communities, Species interactions, Evolution, and The effects of Invasive species in the Great Lakes on these fronts. It is important to note that an invasive species has several critical advantages over Native Animals. Native Animals have exact spots in their food webs, that they evolved specifically for. They have designated predators and or prey. So there are restrictions on their population. Invasive species that manage to gain a foothold tend to be very successful. If they can find a decent food source they tend to lack predators leading to a population explosion. If left unchecked they will wipe out their competition. This can have a devastating effect on the entire food web. In the great lakes this is becoming a real problem as two of the most devastating invasive species feed on the bottom-most level of the food web. This effects the entire population of the great lakes, nothing is immune to these animals. I am of course referring to Asian Carp and Zebra Mussels. These invasive species are competing for Niches occupied by Native Species, and are quite successful. What this means is that if this current trend continues, we could witness a total collapse of the great lakes food web.
According to asiancarp.org, the Asian carp will compete with smaller native fish such as the Cisco, Bloater, and Yellow Perch. These small fish in turn provide the food for larger fish such as Lake Trout and Walleye. (asiancarp.org) Even This minor example shows the danger. These 5 species could easily become extinct, but what does that mean for the Great Lakes. Larger Predators like Trout or Walleye keep the populations of smaller fish in check, if they were to disappear, there would be no population checks on smaller fish which would lead to a population explosion among smaller fish. This would in turn deplete the remaining food source even more rapidly. More fish competing for less and less food. Of course this is not very likely as the asian carp would probably outcompete the smaller fish first and then the larger predators would disappear. But what would this mean? It would mean a total meltdown of the Food web in the great lakes and the death of many Animals that depend on the Great Lakes for food. This problem is increased when you consider that Asian carp will also be wiping out plants and feeding on phytoplankton. With less oxygen production in the Great Lakes, species would be hard pressed to survive. That and the fact that Zebra mussels, which are very similar to Carp in their effects on the great lakes, are also a threat facing the great lakes. The two species in combination could trigger a wave of mass extinction that could wipe out thousands of years of evolution. (the great lakes are are relatively new feature to the North American continent, carved out by glaciers during the ice ages, so they have not had a large amount of time in which evolution could occur). According to asiancarp.org, the establishment of a sustainable population of invasive species is dependent on predator-prey interactions, food availability, and other various factors. (asiancarp.org)
According to ScienceDaily.com, the real threat is not what they will do to the great lakes as a whole but what they will do to the shore area, to the tributaries that enter the lake. Such areas are key breeding grounds for smaller fish. The carp could wipe out the food in these areas and cause tremendous damage to both aquatic species and any terrestrial species that rely on the Great Lakes for food. This fact is backed up by Csmonitor.com who state that successful invasive species breed fast, and eat a lot. (Csmonitor.com). According to Csmonitor.com, asian carp can carry a million eggs in a lifetime, and eat a lot, so a small population of these large fast breeding fish could grow rapidly to become a real problem.
Resources:
http://asiancarp.org/background.asp
http://asiancarp.org/frequently-asked-questions/
http://www.sciencedaily.com/releases/2011/06/110630112859.htm
http://www.csmonitor.com/USA/2010/0316/Asian-carp-how-one-fish-could-ruin-the-Great-Lakes
According to asiancarp.org, the Asian carp will compete with smaller native fish such as the Cisco, Bloater, and Yellow Perch. These small fish in turn provide the food for larger fish such as Lake Trout and Walleye. (asiancarp.org) Even This minor example shows the danger. These 5 species could easily become extinct, but what does that mean for the Great Lakes. Larger Predators like Trout or Walleye keep the populations of smaller fish in check, if they were to disappear, there would be no population checks on smaller fish which would lead to a population explosion among smaller fish. This would in turn deplete the remaining food source even more rapidly. More fish competing for less and less food. Of course this is not very likely as the asian carp would probably outcompete the smaller fish first and then the larger predators would disappear. But what would this mean? It would mean a total meltdown of the Food web in the great lakes and the death of many Animals that depend on the Great Lakes for food. This problem is increased when you consider that Asian carp will also be wiping out plants and feeding on phytoplankton. With less oxygen production in the Great Lakes, species would be hard pressed to survive. That and the fact that Zebra mussels, which are very similar to Carp in their effects on the great lakes, are also a threat facing the great lakes. The two species in combination could trigger a wave of mass extinction that could wipe out thousands of years of evolution. (the great lakes are are relatively new feature to the North American continent, carved out by glaciers during the ice ages, so they have not had a large amount of time in which evolution could occur). According to asiancarp.org, the establishment of a sustainable population of invasive species is dependent on predator-prey interactions, food availability, and other various factors. (asiancarp.org)
According to ScienceDaily.com, the real threat is not what they will do to the great lakes as a whole but what they will do to the shore area, to the tributaries that enter the lake. Such areas are key breeding grounds for smaller fish. The carp could wipe out the food in these areas and cause tremendous damage to both aquatic species and any terrestrial species that rely on the Great Lakes for food. This fact is backed up by Csmonitor.com who state that successful invasive species breed fast, and eat a lot. (Csmonitor.com). According to Csmonitor.com, asian carp can carry a million eggs in a lifetime, and eat a lot, so a small population of these large fast breeding fish could grow rapidly to become a real problem.
Resources:
http://asiancarp.org/background.asp
http://asiancarp.org/frequently-asked-questions/
http://www.sciencedaily.com/releases/2011/06/110630112859.htm
http://www.csmonitor.com/USA/2010/0316/Asian-carp-how-one-fish-could-ruin-the-Great-Lakes
Wednesday, February 1, 2012
Energy and the Great Lakes
Invasive species pose a threat to the stability of the Great Lakes. They threaten the delicate balance that sustains life in the Great Lakes. A good example of this is the Zebra mussel, a small mussel that is very successful in adapting to new environments. According to the Great Lakes Science Center, female mussels can produce a million eggs each year. They remove detritis and small organisms from the water, removing the bottom of the food chain and do this so proficiently that these tiny mussels can clean a gallon of water per day. Combined with massive numbers they are a plague on the great lakes.
So what does this have to do with energy? Among the microscopic particles consumed by mussels are phytoplankton, a critical producer in the aquatic food chain. Removing these in vast quantities prevents other species from eating sufficient food to survive. The Zebra mussels have predators, but not enough to slow their explosive population growth. An interesting fact noted by the Great Lakes Science Center states that Zebra Mussels have increased water clarity in Lake Erie from less than half a foot to over thirty feet in places. This is a grim warning to the rest of the Great Lakes, with Zebra mussels cleaning water that rapidly and efficiently, they could turn the entire expanse of the Great Lakes into a sterile pool unable to support even the smallest native population. The EPA states that at least twenty-five invasive fish species have flooded into the great lakes in the last two-hundred years. Twenty-Five species, and a single mussel is capable of wiping out entire lakes, what could twenty-five do, just imagine it.
As if things were not bad enough for the Great Lakes food web, another threat far larger than mussels and far more dangerous to man is coming. Asian Carp, a fish that, according to Time can weigh a hundred pounds. While that statistic is alarming, the size of the fish is not the threat here, it is its eating habits.
According to the National Park Service a Grass Carp can eat forty percent of its body weight in plants a day. "Asian carp grow fast, consume plants, mussels, snails, and plankton." (National Park Service) Given this information, the carp could be a mixed blessing, they eat mussels and could combat the Zebra mussels, but the fact is they reproduce fast and will out-compete native species causing a wave of extinctions in the Great Lakes should they arrive. As they feed on the lowest levels of the food chain, they represent a significant threat to the stability of the Great Lakes.
Sources:
http://www.glsc.usgs.gov/main.php?content=research_invasive_zebramussel&title=Invasive%20Invertebrates0&menu=research_invasive_i
http://www.epa.gov/glnpo/invasive/
http://www.time.com/time/health/article/0,8599,1962108,00.html
http://www.nps.gov/miss/naturescience/ascarpover.htm
So what does this have to do with energy? Among the microscopic particles consumed by mussels are phytoplankton, a critical producer in the aquatic food chain. Removing these in vast quantities prevents other species from eating sufficient food to survive. The Zebra mussels have predators, but not enough to slow their explosive population growth. An interesting fact noted by the Great Lakes Science Center states that Zebra Mussels have increased water clarity in Lake Erie from less than half a foot to over thirty feet in places. This is a grim warning to the rest of the Great Lakes, with Zebra mussels cleaning water that rapidly and efficiently, they could turn the entire expanse of the Great Lakes into a sterile pool unable to support even the smallest native population. The EPA states that at least twenty-five invasive fish species have flooded into the great lakes in the last two-hundred years. Twenty-Five species, and a single mussel is capable of wiping out entire lakes, what could twenty-five do, just imagine it.
As if things were not bad enough for the Great Lakes food web, another threat far larger than mussels and far more dangerous to man is coming. Asian Carp, a fish that, according to Time can weigh a hundred pounds. While that statistic is alarming, the size of the fish is not the threat here, it is its eating habits.
According to the National Park Service a Grass Carp can eat forty percent of its body weight in plants a day. "Asian carp grow fast, consume plants, mussels, snails, and plankton." (National Park Service) Given this information, the carp could be a mixed blessing, they eat mussels and could combat the Zebra mussels, but the fact is they reproduce fast and will out-compete native species causing a wave of extinctions in the Great Lakes should they arrive. As they feed on the lowest levels of the food chain, they represent a significant threat to the stability of the Great Lakes.
Sources:
http://www.glsc.usgs.gov/main.php?content=research_invasive_zebramussel&title=Invasive%20Invertebrates0&menu=research_invasive_i
http://www.epa.gov/glnpo/invasive/
http://www.time.com/time/health/article/0,8599,1962108,00.html
http://www.nps.gov/miss/naturescience/ascarpover.htm
Tuesday, January 24, 2012
Choosing a topic
This blog will discuss many of the following topics: the effects of invasive species on the native population and the health of the lakes in general, The various invasive species themselves, and measures to reduce or eliminate them from the great lakes. Zebra mussels, Asian Carp, lampreys, and other invasive species threaten the great lakes. Mussels, and Asian Carp represent a significant threat as they remove phytoplankton, zooplankton, and detritus which represent the bottom of the aquatic food chain. They could turn the great lakes into a sterile pool of water unable to support life unless something is done to check their populations.
Until next time,
Brian Kober
Until next time,
Brian Kober
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